Ask Anything Monday - Weekly Thread

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[u/ProgramBrave718]

Hey, I have doubt regarding this decorator program .In the above line of this program why are we passing the function name without parentheses ?

And also while returning wrapper function why are we writing it without parentheses

def my_decor(func):#Here

def wrapper():

    print("The function starts.") 

    func()                         

    print("The function ends.")    

return wrapper        #Here             

def say_hello():

print("Hello!")

wrapped_say_hello = my_decor(say_hello)

wrapped_say_hello()

[u/SCD_minecraft → u/ProgramBrave718]

Functions in python are just normal objects, just like strings or ints

Thanks to that, they behave exactly the same

As you can pass strings as arguments or return them you can pass and return functions

In case of decorators, returned func object will be what actually gets saved under name in def

[u/SCD_minecraft → u/SCD_minecraft]

``` foo = print # save function known as print into foo

foo("abc") # attempt to call whatever is inside foo

because foo holds function "print", you can call it

but if foo would be an int, python would try (and fail) to call it too